package cn.hybris.common.util;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;

import org.apache.xml.security.signature.XMLSignatureInput;
import org.apache.xml.security.utils.resolver.ResourceResolverException;
import org.apache.xml.security.utils.resolver.ResourceResolverSpi;
import org.apache.xml.utils.URI;
import org.w3c.dom.Attr;

/**
 * This class helps us home users to resolve http URIs without a network
 * connection.
 * 
 * @author yang.ly
 */
public class OfflineResolver extends ResourceResolverSpi {
	/** {@link org.apache.commons.logging} logging facility */

	/** Field _uriMap */
	static Map<String, String> _uriMap = null;

	/** Field _mimeMap */
	static Map<String, String> _mimeMap = null;

	static {
		org.apache.xml.security.Init.init();

		_uriMap = new HashMap<String, String>();
		_mimeMap = new HashMap<String, String>();

		OfflineResolver.register("http://www.w3.org/TR/xml-stylesheet", "data/org/w3c/www/TR/xml-stylesheet.html",
				"text/html");
		OfflineResolver.register("http://www.w3.org/TR/2000/REC-xml-20001006",
				"data/org/w3c/www/TR/2000/REC-xml-20001006", "text/xml");
		OfflineResolver.register("http://www.nue.et-inf.uni-siegen.de/index.html",
				"data/org/apache/xml/security/temp/nuehomepage", "text/html");
		OfflineResolver.register("http://www.nue.et-inf.uni-siegen.de/~geuer-pollmann/id2.xml",
				"data/org/apache/xml/security/temp/id2.xml", "text/xml");
		OfflineResolver.register("http://xmldsig.pothole.com/xml-stylesheet.txt",
				"data/com/pothole/xmldsig/xml-stylesheet.txt", "text/xml");
		OfflineResolver.register("http://www.w3.org/Signature/2002/04/xml-stylesheet.b64",
				"data/ie/baltimore/merlin-examples/merlin-xmldsig-twenty-three/xml-stylesheet.b64", "text/plain");
	}

	/**
	 * Method engineResolve.
	 * 
	 * @param uri
	 * @param BaseURI
	 * 
	 * @throws ResourceResolverException
	 */
	public XMLSignatureInput engineResolve(Attr uri, String BaseURI) throws ResourceResolverException {

		InputStream is = null;
		try {
			String URI = uri.getNodeValue();

			if (OfflineResolver._uriMap.containsKey(URI)) {
				String newURI = (String) OfflineResolver._uriMap.get(URI);

				is = new FileInputStream(newURI);

				XMLSignatureInput result = new XMLSignatureInput(is);

				result.setSourceURI(URI);
				result.setMIMEType((String) OfflineResolver._mimeMap.get(URI));

				return result;
			} else {
				Object exArgs[] = { "The URI " + URI + " is not configured for offline work" };

				throw new ResourceResolverException("generic.EmptyMessage", exArgs, uri, BaseURI);
			}
		} catch (IOException ex) {
			throw new ResourceResolverException("generic.EmptyMessage", ex, uri, BaseURI);
		} finally {
			if (is != null) {
				try {
					is.close();
				} catch (IOException e) {
				}
			}
		}
	}

	/**
	 * We resolve http URIs <I>without</I> fragment.
	 * 
	 * @param uri
	 * @param BaseURI
	 */
	public boolean engineCanResolve(Attr uri, String BaseURI) {
		String uriNodeValue = uri.getNodeValue();

		if (uriNodeValue == null || "".equals(uriNodeValue) || uriNodeValue.startsWith("#")) {
			return false;
		}

		try {
			URI uriNew = new URI(new URI(BaseURI), uri.getNodeValue());
			if (uriNew.getScheme().equals("http")) {

				return true;
			}
		} catch (URI.MalformedURIException ex) {
		}

		return false;
	}

	/**
	 * Method register.
	 * 
	 * @param URI
	 * @param filename
	 * @param MIME
	 */
	private static void register(String URI, String filename, String MIME) {
		_uriMap.put(URI, filename);
		_mimeMap.put(URI, MIME);
	}

}
